High school teachers who engage students through active learning in their classrooms can more fully understand this instructional practice by examining the theories and strategies underlying the cognitive perspective of educational psychology, which addresses the development of knowledge in the individual mind. Two theoretical explanations, psychological constructivism and information processing, promote learning as a constructive process that can be aided by strategies such as activating prior knowledge, chunking, elaborating, and invoking a schema. High school teachers can use these cognitive active learning strategies in classroom instruction or incorporate them into out-of-class assignments to increase students engagement in their learning. (Contains 3 notes.)